WO2004113967A1 - Resin optical component and process for producing the same - Google Patents

Abstract

A process for producing a resin optical component in which a light shielding layer can be formed easily. A laser light is focused at an arbitrary position within resin exhibiting a high light transmittance and energy is concentrated thereat, thus generating a micro-spotty discolored part through carbonization of resin. A light shielding wall exhibiting a high light absorbance is formed within the resin exhibiting a high light transmittance by forming a multiplicity of micro-spotty discolored parts within the resin. The light shielding wall can remove a stray light, i.e. a light incident obliquely to a lens, passing through a lens array plate in the thickness direction and leaving a proximate lens at the outgoing side thereof.

Description

 Specification

 Resin-based optical component and its manufacturing method

 The present invention relates to a resin optical component and a method for manufacturing the same, and more particularly, to a resin lens array plate and a method for manufacturing the same. Background technology

 Conventionally, a resin lens array plate, which is an optical component with an aperture stop and a light-blocking function to prevent stray light, has a structure in which a light-blocking layer made of a light-absorbing film is formed between adjacent minute lenses. And a structure in which a light-shielding layer is formed on the surface opposite to the microlens surface. This method of forming the light-shielding layer uses a photo resist containing a light-absorbing agent. (See Japanese Patent Application Laid-Open No. 2002-276710), a light-absorbing paint is applied to the entire surface of the lens, and only the light-absorbing paint on the lens portion is applied. A method of forming by removing (refer to Japanese Patent Application Laid-Open No. 2001-318102), a method of applying a light-absorbing paint to a portion where a light-shielding layer is to be formed by an ink jet method ( Japanese Unexamined Patent Publication No. 2001-33009), a groove is formed in a portion where a light shielding layer is formed, A method of filling the grooves with a light-absorbing paint has been proposed.

However, the conventional technology has a problem that an effective stray light removal cannot be obtained with a light-shielding layer provided on the surface of a lens array plate or a surface facing the lens surface. The reason for this is that if a light-blocking layer is formed around the lens and between adjacent lenses, or on the surface facing the lens surface, removal of light incident from outside the lens area or light obliquely incident on the lens may occur. Although effective for removing light emitted from outside the lens area, light obliquely incident on the lens passes through the thickness direction of the lens array plate and exits from the exit side of the adjacent lens. Stray light This is because it cannot be removed. For this reason, in a display device using such a lens array plate, a problem such as a ghost image or poor resolution occurs.

 Also, the method of forming a light-shielding layer by filling a groove with a light-absorbing paint has a problem that the process becomes complicated. Disclosure of the invention

 Therefore, an object of the present invention is to solve the above-mentioned problems and to provide a resin optical component capable of effectively removing stray light.

 Another object of the present invention is to provide a method of manufacturing a resin optical component in which a light shielding layer can be easily formed.

 A first aspect of the present invention is a resin optical component. This resin optical component is formed of a resin that has high transmittance to light in the required wavelength band. Inside the resin, the resin portion that has been discolored by the energy in the absorption wavelength band of the resin becomes a part with high light absorption. Is formed.

 A second aspect of the present invention is a method for producing a resinous optical component made of a resin having high transparency to light in a necessary wavelength band. According to this manufacturing method, energy in an absorption wavelength band of the resin is supplied from the energy supply means to the inside of the resin, and a part of the resin is discolored by the supplied energy to form a portion having high light absorption. . BRIEF DESCRIPTION OF THE FIGURES

 FIG. 1A is a plan view of the resin lens array plate of the present invention. FIG. 1B is a cross-sectional view taken along line XX of FIG. 1A.

 FIG. 2 is a plan view of a part of the resin lens array plate main body. FIG. 3A is a plan view for explaining formation of a light shielding wall.

 FIG. 3B is a sectional view taken along line YY of FIG. 3A.

 FIG. 4 is a cross-sectional view for explaining formation of a low reflection coating.

FIG. 5 is a plan view for explaining formation of a light absorbing film. BEST MODE FOR CARRYING OUT THE INVENTION

 Hereinafter, examples of the resin lens array plate which is the resin optical component of the present invention will be described.

 FIG. 1A is an erect image display device according to the present invention, which is used in an aerial display device for displaying a three-dimensional image or a two-dimensional image on an aerial display device, an image transmitting device for storing an image on a light receiving element or a photoconductor, or the like. FIG. 1B is a plan view of a rectangular resin lens array plate 10 constituting the lens array, and FIG. 1B is a cross-sectional view taken along line XX of FIG. 1A.

 The material of the plate main body 1 constituting the resin lens array plate 10 is desirably a material that can be used for injection molding, has high light transmittance for light in a necessary wavelength band, and has low water absorption. In this embodiment, a cycloolefin resin is used. Each of the plates 10 has a lens forming region at the center on both sides thereof, and spherical micro convex lenses 2 are arranged in a dense structure. In the illustrated example, the lens array shows a case of a hexagonal array in which the aberration at the peripheral portion of the lens can be reduced and the amount of transmitted light increases. The hexagonal array is an array extending in six directions when viewed from one microconvex lens. In a dense structure, the shape of the microconvex lens is a regular hexagon.

 In addition, the arrangement of the optical axes of the minute convex lenses 2 formed on both surfaces of the lens array plate main body 1 is designed to match on both surfaces.

 A high light-absorbing portion is formed inside the resin between the adjacent minute convex lenses, and this portion forms a light shielding wall 7 for removing stray light. The light-shielding wall 7 is along a vertical bisector of a line connecting the centers of the adjacent micro-convex lenses 2, that is, at a boundary position of the micro-convex lens, about 0.05 mm in width and about 0.1 mm from the surface. Formed up to a depth of.

 The depth of the light shielding wall 7 is required to be 13 or more of the thickness of the lens array plate main body 1. If the depth is less than 1 Z3, stray light will leak.

A low-reflection coating 3 is formed on the surface of the lens array plate main body 1 to reduce the reflectance of the resin lens array plate 10. You. A material having a lower refractive index than the lens array plate body 1 can be used for the low reflection coating. In addition to silica compounds, for example, fluorine resins are also used. By forming such a low reflection coating 3, the light transmittance of the lens array plate main body 1 does not decrease.

 Outside the lens forming area on one side of the plate body 1, a masking is formed by a light absorbing film 4 for preventing stray light from entering from other than the lens. Masking may be formed on both sides of the lens array plate main body 1. In this case, a more effective effect of preventing stray light outside the lens formation region can be obtained.

 In the above embodiment, the low reflection coating 3 and the light absorbing film 14 are formed, but these are not necessarily required.

 According to the resin lens array plate 10 having the above configuration, a portion having high light absorption is formed inside the resin between the adjacent micro convex lenses, and this portion forms a light shielding wall for removing stray light. Thus, stray light obliquely incident on the lens can be effectively removed.

 In the above embodiments, the resin lens array plate was manufactured using cycloolefin-based resin, but other resins such as olefin-based resin and norbornene-based resin can also be used. Commercially available products of each resin include ZONEX (registered trademark) @Zeonor (registered trademark) manufactured by Zeon Corporation, and Aaton (registered trademark) manufactured by JSR Corporation.

 Although the shape of the micro convex lens is spherical, an aspherical shape is also conceivable.

 Also, the arrangement of the micro convex lenses may be a dense structure arrangement of a tetragonal arrangement. The tetragonal array is an array extending in four directions when viewed from one microconvex lens. In a dense structure, the shape of the microconvex lens is a square.

Furthermore, the arrangement of the lenticules is not a dense structure but a lens arrangement. An arrangement of a non-dense structure having gaps between the cells may be used. In this case, the shape of the minute convex lens is typically circular, but is not limited to this. In the case of an arrangement of a non-dense structure having a gap between the lenses, a light-shielding wall can be formed between the outer circumferences of the minute convex lenses.

 The micro convex lens may be formed on one side of the resin lens array plate in addition to the mode formed on both sides of the resin lens array plate.

 Further, the lens may have a semi-cylindrical (camel-shaped) shape, and may be arranged parallel or at a predetermined angle to the outer periphery of the resin lens array plate.

 As a method for preventing stray light from entering from a region other than the lens formation region, there is a mode in which a light-absorbing aperture frame is provided. This frame has an opening that does not cover the lens forming region.

 Next, a method of manufacturing the resin lens array plate 10 described with reference to FIG. 1 will be described.

 First, the resin lens array plate main body 1 is manufactured by injection molding. In this embodiment, the lens array plate main body 1 is manufactured using cycloolefin resin. FIG. 2 shows a part of the manufactured lens array plate body 1.

 The lens array plate main body 1 manufactured by injection molding has a lens forming region at the center of both sides of the plate, and the spherical micro convex lens 2 is arranged in a dense structure.

 Next, a method of forming a light shielding wall inside the lens array plate main body 1 is shown in FIGS. 3A and 3B. FIG. 3A is a plan view, and FIG. 3B is a sectional view taken along line YY of FIG. 3A.

The light-shielding wall is formed by discoloring the resin, and the energy in the absorption wavelength band of the resin is used as the energy for discoloring the resin. In this embodiment, laser light is used. The laser beam is focused at an arbitrary position inside the resin with high light transmittance, and the energy is concentrated, thereby causing minute dot-like discoloration due to carbonization of the resin. When the micro convex lens 2 is arranged in a hexagonal close-packed structure, as shown in FIGS. 3A and 3B, a laser beam 5 is applied to the boundary position of the lens. YV 0 ₄ as a energy source, using a laser oscillator, a laser beam having a wavelength of 5 3 2 nm. The laser irradiation conditions are preferably pulse oscillation with an output of 0.7 to 1.7 kW and a frequency of 10 to LOO kHz. In this embodiment, the output 1 k W, a frequency 2 0 k H _Z, a laser beam condensed into a bi one Musupo' preparative diameter phi theta. 0 1 mm, the resin lens array plates body 1 center depth Focus on the position.

 By irradiating the laser beam while scanning it several times at a scanning speed of 800 mmZ sec, a large number of minute spot-like discoloration parts 6 due to carbonization of the resin are formed at the part where the light shielding wall is formed. I do.

 The discoloration portions 6 are formed so as to be distributed on the near side and the back side of the irradiation optical axis with the focus on the position where the laser beam is focused. By forming a large number of these minute dot-like discolored portions 6 inside the resin, a light-absorbing light-shielding wall 7 is formed inside the resin having a high light transmittance.

 The width of the formed light shielding wall 7 is about 0.05 mm, and the depth from the surface is about 0.1 mm. This depth is at least 13 times the thickness of the plate body.

 In the case of a non-dense structure in which there is a gap between the lenses, a light-shielding wall is formed along the outer periphery of the minute convex lens.

Next, as shown in FIG. 4, a low reflection coating 3 is formed on the surface of the resin lens array plate main body 1 in order to reduce the reflectance of the resin lens array plate. The low-reflection coating 3 contacts the lens-forming region of the lens array plate body 1 with an aqueous solution of hydrosilicofluoric acid (H ₂ Si F ₆ ) in which silica (Si 0 ₂ ) is supersaturated, for example. As a result, a low-reflection film made of a silica compound film is formed.

Next, as shown in FIG. 5, masking with a light-absorbing film 4 is performed outside the lens forming area on one side of the lens array plate main body 1 to prevent stray light from entering other than the lens. Form. in this case, The light-absorbing film is made of a light-reactive material, for example, a black resist containing carbon, and after forming the light-absorbing film on the area including the lens forming area of the lens array plate main body 1 or on the entire surface, Masking outside the lens forming area is formed by photolithography. In this embodiment, injection molding is used to form the lens array plate. However, the present invention is not limited to this. Alternatively, a plate may be formed by extrusion molding, and minute convex lenses may be formed on both surfaces by an embossing method. In this case, a light-shielding wall may be formed by laser light on a plate manufactured by extrusion molding, and then a micro convex lens may be formed by an embossing method.

 When a low-reflection film and a light-absorbing film are not required, these forming steps are unnecessary. Industrial applicability

 According to the present invention, since the light-shielding wall constituted by the portion discolored by the energy is formed inside the resin of the resin lens array plate, the light obliquely incident on the lens is shielded from light. It is blocked by a wall and does not enter a nearby lens as stray light. Since stray light can be effectively removed in this way, a display device using the resin lens array plate of the present invention does not cause a ghost image or a problem when the resolution is poor.

 Further, according to the manufacturing method of the present invention, since the light-shielding wall is formed by irradiating the resin with energy such as a laser beam, the resin can be easily formed without going through a complicated process.

Claims

Range of request 1. Indispensable resin optical components made of resin with high transmittance for light in the required wavelength band.  The resin has a resin portion discolored by energy in an absorption wavelength band of the resin, and the discolored resin portion absorbs light.  One bite A resin optical component characterized in that it forms a highly functional part. 2. The resinous optical component is a resin lens having a spherical or aspherical micro convex lens formed thereon,  The resin optical component according to claim 1, wherein the high light-absorbing portion is formed inside the resin outside a region through which light is transmitted, and constitutes a light-shielding wall that removes stray light. . 3. The resin optical component is a resin lens array in which spherical or aspherical minute convex lenses are arranged at a predetermined pitch on a flat plate.  The resin optical component according to claim 1, wherein the high light-absorbing portion is formed inside a resin between adjacent minute convex lenses, and forms a light shielding wall for removing stray light. 4. The resin optical component is a resin lens array plate in which spherical or aspherical minute convex lenses are arranged at a predetermined pitch on a flat plate. The resin optical component according to claim 1, wherein the high light-absorbing portion is formed in a resin between adjacent microconvex lenses and forms a light-shielding wall for removing stray light. Note-The light-shielding wall is placed on the resin lens array plate from the lens side surface. The resin optical component according to claim 3, wherein the resin optical component is formed over a thickness of 1 Z 3 or more in one thickness direction. 6. The resinous optical component according to any one of claims 1 to 4, wherein the resin is a cycloolefin-based resin, an olefin-based resin, or a norbornene-based resin. 7. In the method of manufacturing a resinous optical component made of a resin having high transmittance for light in a necessary wavelength band,  An energy in an absorption wavelength band of the resin is supplied from an energy supply unit into the resin,  A method for producing a resinous optical component, wherein a part of the resin is discolored by the supplied energy to form a portion having high light absorption. . 8. The method for manufacturing a resin optical component according to claim 7, wherein the energy is light or radiation. 9. The method for producing a resin optical component according to claim 8, wherein the energy is a laser beam. 10. The resin optical component is a resin lens on which a spherical or aspherical micro convex lens is formed.  The resin optical component according to claim 7, wherein the high light-absorbing portion is formed inside the resin outside a region through which light is transmitted, and constitutes a light-shielding wall that removes stray light. Manufacturing method. 1 1. The resin optical component is a resin lens array plate in which spherical or aspherical micro convex lenses are arranged at a predetermined pitch on a flat plate. And  The resin optical component according to claim 7, wherein the high light-absorbing portion is formed inside a resin between adjacent minute convex lenses, and forms a light-shielding wall for removing stray light. Production method. 12. The resin optical component is a resin lens array in which spherical or aspherical minute convex lenses are arranged at a predetermined pitch on a flat plate.  The resin optical component according to claim 7, wherein the high light-absorbing portion is formed in a resin between adjacent microconvex lenses and forms a light-shielding wall for removing stray light. Production method. 13. The resin according to claim 11, wherein the light-shielding wall is formed on a lens-side surface and extends in a thickness direction of the resin lens array over a thickness of 13 or more. Manufacturing method of conductive optical parts. 14. The method for producing a resinous optical component according to any one of claims 7 to 12, wherein the resin is a cycloolefin-based resin, an olefin-based resin, or a norbornene-based resin.